Balloon catheter with deformable fluid delivery conduit

ABSTRACT

A medical device, including an elongate body having a proximal portion and a distal portion; a shaft at least partially disposed within the elongate body; an expandable element at the distal portion of the elongate body; and a fluid delivery conduit defining a deflectable segment movably coupled to the shaft, the deflectable segment being transitionable from a substantially linear configuration to a substantially curvilinear configuration.

CROSS-REFERENCE TO RELATED APPLICATION

This application is related to and claims priority to U.S. Utilitypatent application Ser. No. 12/910492, filed Oct. 22, 2010, entitledBALLOON CATHETER WITH DEFORMABLE FLUID DELIVERY CONDUIT, the entirety ofwhich is incorporated herein by reference.

STATEMENT REGARDING FEDERALLY SPONSORED RESEARCH OR DEVELOPMENT

n/a

FIELD OF THE INVENTION

The present invention relates to a method and system for tissuetreatment, and in particular, towards systems and methods of use thereoffor thermally ablating cardiac tissue.

BACKGROUND OF THE INVENTION

Minimally invasive devices, such as catheters, are often employed formedical procedures, including those involving mapping, ablation,dilation, and the like. In a particular situation, an ablation proceduremay involve creating a series of inter-connecting or otherwisesubstantially continuous lesions in order to electrically isolate tissuebelieved to be the source of an arrhythmia. During the course of such aprocedure, a physician may employ several different catheters havingvariations in the geometry and/or dimensions of the ablative element inorder to produce the desired ablation pattern and/or continuity. Eachcatheter may have a unique geometry for creating a specific lesion orpattern, with the multiple catheters being sequentially removed andreplaced during a designated procedure to create the desired multiplelesions constituting a pattern or continuous segment of treated tissue.In addition, a selected device may have a substantially fixed geometryor dimension for a specific application and as such, may be limited touse in situations where the fixed dimensions of the device areappropriate. However, variations in the dimensions or characteristics ofphysiological structures may vary from patient to patient, rendering adevice with specific dimensions or fixed configuration ineffectiveand/or difficult to use. As such, multiple devices having a range ofvarying fixed dimensions may be needed to successfully perform a desiredtreatment. Exchanging these various devices during a procedure can causeinaccuracies or movement in the placement and location of the distal tipwith respect to the tissue to be ablated, and may further add to thetime required to perform the desired treatment. These potentialinaccuracies and extended duration of the particular procedure, not tomention the risks of complications from repeatedly inserting andretracting devices to and from an incision site, increase the risk tothe patient undergoing treatment.

In addition to the inefficiencies and risks associated with usingmultiple devices to perform a procedure, the efficacy of certaintreatment procedures, such as those involving thermal energy transfer,may be limited by poor thermal conductivity between a device and thetissue site. To provide shorter treatment durations and increasedefficacy for the particular treatment provided, it is desirable tooptimize the heat transfer between the specific tissue to be treated andthe cryogenic element or device. In other words, heat transfer from anytissue other than that selected for treatment, such as blood or otherbody fluids in or passing through the vicinity of the cryogenic elementfor example, should be minimized or avoided. Such thermal exchange withtissues or fluids other than that targeted for treatment can reduce thethermal exchange with the targeted tissue and also require additional“cooling power” or refrigerant flow in the case of cryogenic cooling inorder to complete the desired treatment. Accordingly, heat transfer withany thermal load other than the tissue to be treated should be reducedor prevented.

Accordingly, in light of the above limitations, it would be desirable toprovide a medical device in which the particular size, shape, and/ordimensions of the device may be controlled and modified during use toprovide ablative patterns or treatment delivery characteristics ofvarious shapes and continuity, without the need for additional cathetersor the like having a single geometric orientation that is limited in itsability to provide multiple ablative patterns or treatmentcharacteristics for a specific tissue region. It would also be desirableto provide an apparatus and methods of use thereof having increased heattransfer efficiency during thermal exchange procedures.

SUMMARY OF THE INVENTION

The present invention advantageously provides a medical system andmethods of use thereof in which the particular size, shape, and/ordimensions of the components of the system may be controlled andmodified during use to provide ablative patterns or treatment deliverycharacteristics of various shapes and continuity, as well as havingincreased heat transfer efficiency during thermal exchange procedures.In particular, a medical device is disclosed, including an elongate bodyhaving a proximal portion and a distal portion; a shaft at leastpartially disposed within the elongate body; an expandable element atthe distal portion of the elongate body; and a fluid delivery conduitdefining a deflectable segment movably coupled to the shaft, thedeflectable segment being transitionable from a substantially linearconfiguration to a substantially curvilinear configuration. The fluiddelivery conduit may define at least one helical opening, the device mayinclude a cryogenic coolant source in fluid communication with the fluiddelivery conduit, and the shaft may be movable with respect to theelongate body and define a lumen therein for passage of a guide wire.The elongate body may define an exhaust lumen in fluid communicationwith an interior of the expandable element, and the deflectable segmentmay define a proximal end and a distal end, the proximal end beingslidably and rotatably coupled to the shaft, where the distal end isimmovably fixed to the shaft. The device may also include a firstactuator coupled to the deflectable segment to adjust a longitudinalposition of at least a portion of the deflectable segment and a secondactuator coupled to the deflectable segment to adjust a rotationalposition of at least a portion of the deflectable segment.

A method of thermally treating tissue is disclosed, includingpositioning an expandable element of a medical device adjacent to thetissue; delivering a fluid into an interior of the expandable elementwith a fluid delivery conduit to expand the expandable element, thefluid delivery conduit being in a first geometric configuration;thermally treating a first region of the tissue with the expandableelement; transitioning the fluid delivery conduit from the firstgeometric configuration into a second geometric configuration; andthermally treating a second region of the tissue with the expandableelement. The first geometric configuration may be substantially linearand the second geometric configuration may be curvilinear The firstregion may have a shape different from a shape of the second region,where the shape of the first region is substantially circular.Transitioning the fluid delivery conduit from the first geometricconfiguration into a second geometric configuration may include rotatingat least a portion of the fluid delivery conduit about a guide wirelumen of the medical device and/or longitudinally sliding at least aportion of the fluid delivery conduit along a guide wire lumen of themedical device. Delivering a fluid may include extending a portion ofthe fluid delivery conduit defining at least on helical opening toincrease a rate of fluid flow into the expandable element and/orcompressing a portion of the fluid delivery conduit defining at least onhelical opening to decrease a rate of fluid flow into the expandableelement. Thermally treating the tissue may include ablating at least aportion of the tissue, and the tissue includes an ostium of a pulmonaryvein, and the method may also include terminating coolant dispersioninto the interior cavity; transitioning the fluid delivery conduit fromthe second geometric configuration to the first configuration; andremoving the expandable element from the tissue.

BRIEF DESCRIPTION OF THE DRAWINGS

A more complete understanding of the present invention, and theattendant advantages and features thereof, will be more readilyunderstood by reference to the following detailed description whenconsidered in conjunction with the accompanying drawings wherein:

FIG. 1 is an illustration of an embodiment of a medical systemconstructed in accordance with the principles of the present invention;

FIG. 2 is an illustration of a distal-to-proximal view of the medicaldevice of the system of FIG. 1;

FIG. 3 is an illustration of an embodiment of a medical deviceconstructed in accordance with the principles of the present invention;

FIG. 4 is an additional illustration of the medical device of FIG. 3;

FIG. 5 is an illustration of an exemplary use of an embodiment of amedical system in accordance with the principles of the presentinvention; and

FIG. 6 is another illustration of an exemplary use of an embodiment of amedical system in accordance with the principles of the presentinvention

DETAILED DESCRIPTION OF THE INVENTION

The present invention advantageously provides a medical system andmethods of use thereof in which the particular size, shape, and/ordimensions of the components of the system may be controlled andmodified during use to provide ablative patterns or treatment deliverycharacteristics of various shapes and continuity, as well as havingincreased heat transfer efficiency during thermal exchange procedures.Referring now to the drawing figures in which like referencedesignations refer to like elements, an embodiment of a medical systemconstructed in accordance with principles of the present invention isshown in FIG. 1 and generally designated as “10.” The system 10generally includes a medical device 12 that may be coupled to a controlunit 14 or operating console. The medical device 12 may generallyinclude one or more treatment regions for energetic or other therapeuticinteraction between the medical device 12 and a treatment site. Thetreatment region(s) may deliver, for example, cryogenic therapy,radiofrequency energy, or other energetic transfer with a tissue area inproximity to the treatment region(s), including cardiac tissue.

Now referring to FIGS. 1-2, the medical device 12 may include anelongate body 16 passable through a patient's vasculature and/orproximate to a tissue region for diagnosis or treatment, such as acatheter, sheath, or intravascular introducer. The elongate body 16 maydefine a proximal portion 18 and a distal portion 20, and may furtherinclude one or more lumens disposed within the elongate body 16 therebyproviding mechanical, electrical, and/or fluid communication between theproximal portion of the elongate body 16 and the distal portion of theelongate body 16, as discussed in more detail below.

The medical device 12 may include a shaft 22 at least partially disposedwithin a portion of the elongate body 16. The shaft 22 may extend orotherwise protrude from a distal end of the elongate body 16, and may bemovable with respect to the elongate body 16 in longitudinal androtational directions. That is, the shaft 22 may be slidably and/orrotatably moveable with respect to the elongate body 16. The shaft 22may further define a lumen 24 therein for the introduction and passageof a guide wire. The shaft 22 may include or otherwise be coupled to adistal tip 26 that defines an opening and passage therethrough for theguide wire.

The medical device 12 may further include a fluid delivery conduit 28traversing at least a portion of the elongate body and towards thedistal portion. The delivery conduit 28 may be coupled to or otherwiseextend from the distal portion of the elongate body 16, and may furtherbe coupled to the shaft 22 and/or distal tip of the medical device 12.The fluid delivery conduit 28 may be flexible, constructed from a shapememory material (such as Nitinol), and/or include other controllablydeformable materials that allow the fluid delivery conduit 28 to bemanipulated into a plurality of different geometric configurations,shapes, and/or dimensions. The fluid delivery conduit may further definea deflectable segment 30 at the distal portion of the device that can becontrollably transitioned into a variety of different configurations. Inparticular, the deflectable segment 30 may include a distal end 32 and aproximal end 34 and a length therebetween. The proximal and/or distalends of the deflectable segment 30 may be slidably and/or rotatablycoupled to the elongate body 16, the shaft 22, and/or the distal tip 26to allow the deflectable segment 30 to be configured into differentconfigurations ranging from substantially linear (as shown in FIG. 1) tosubstantially helical or circumferential (as shown in FIG. 2), forexample. Particular examples of combinations of the movable nature ofthe deflectable segment 30 of the fluid delivery conduit 28 mayinclude 1) an anchored proximal end 34 with a slidable and/or rotatabledistal end 32 with respect to the shaft 22 and/or distal tip 26; 2) ananchored distal end 32 and a slidable and/or rotatable proximal end 34with respect to the shaft 22 and/or elongate body 16; or 3) both theproximal and distal ends are slidable and/or rotatable with respect tothe shaft 22, elongate body 16 and/or distal tip 26. The controllablemovement of the proximal and distal ends may be achieved or otherwiseimplemented through the use of one or more deflection control elements36 coupled to the proximal and/or distal ends of the deflectable segment30 and that further coupled to a proximal portion of the medical deviceaccessible to an end user or physician. The deflection control elements36 may include, for example, one or more steering wires, torquetransmission structures, or other linkage engageable with thedeflectable segment 30. The example in FIG. 1 illustrates the proximaland distal ends of the deflectable segment 30 being both rotatably andslidably coupled to the shaft. However, configurations where either thedistal or proximal ends are securely anchored or fixed with respect tothe shaft or elongate body while still allowing a desired degree ofdeflection, manipulation, and/or steering is also contemplated, asdescribed herein.

The fluid delivery conduit 28 may define a lumen therein for the passageor delivery of a fluid from the proximal portion of the elongate body 16and/or the control unit 14 to the distal portion and/or treatment regionof the medical device 12. The fluid delivery conduit 28 may furtherinclude one or more apertures or openings 38 therein, such as in thedeflectable segment 30, to provide for the dispersion or directedejection of fluid from the lumen to an environment exterior to the fluiddelivery conduit 28. As shown in FIGS. 3 and 4, the openings 38 may behelically arranged around an outer circumference of the fluid deliveryconduit, providing for a segment of the delivery conduit 28 that isextendable or collapsible to at least partially control the fluiddispersion. For example, when the portion of the fluid delivery conduit28 containing the helical openings experiences a compressing force ormanipulation, the size of the helical openings (e.g., the spacingbetween the walls of the fluid delivery conduit defining the helicalopenings) is controllably reduced or altogether eliminated, thusreducing or eliminating fluid flow out of the fluid delivery conduit.Oppositely, when the portion of the fluid delivery conduit 28 containingthe helical openings experiences an extension or “stretching” force, thesize of the helical openings (e.g., the spacing between the walls of thefluid delivery conduit defining the helical openings) is controllablyincreased, thus increasing fluid flow out of the fluid delivery conduit.The extension and compression of the fluid delivery tube 28 can beachieved through manipulation of one or more of the deflection controlelements 36, as described herein.

Again referring to FIGS. 1 and 2, the medical device 12 may furtherinclude an expandable element 40 at the distal portion of the elongatebody 16. The expandable element 40 may be coupled to a portion of theelongate body 16 and also coupled to a portion of the shaft 22 and/ordistal tip 26 to contain a portion of the fluid delivery conduit 28therein. The expandable element 40 defines an interior chamber or regionthat contains coolant or fluid dispersed from the fluid delivery conduit28, and may be in fluid communication with an exhaust lumen 42 definedby or included in the elongate body 16 for the removal of dispersedcoolant from the interior of the expandable element 40. The expandableelement 40 may further include one or more material layers providing forpuncture resistance, radiopacity, or the like.

The medical device 12 may include a handle 44 coupled to the proximalportion of the elongate body 16. The handle 44 can include circuitry foridentification and/or use in controlling of the medical device 12 oranother component of the system. For example, the handle 44 may includeone or more pressure sensors 46 to monitor the fluid pressure within themedical device 12. Additionally, the handle 44 may be provided with afitting 48 for receiving a guide wire that may be passed into the guidewire lumen 24. The handle 44 may also include connectors 50 that arematable directly to a fluid supply/exhaust and control unit 14 orindirectly by way of one or more umbilicals. The handle 44 may furtherinclude blood detection circuitry in fluid and/or optical communicationwith the injection, exhaust and/or interstitial lumens. The handle 44may also include a pressure relief valve in fluid communication with thefluid delivery conduit 28 and/or exhaust lumen to automatically openunder a predetermined threshold value in the event that value isexceeded.

The handle 44 may also include one or more actuation or control featuresthat allow a user to control, deflect, steer, or otherwise manipulate adistal portion of the medical device from the proximal portion of themedical device. For example, the handle 44 may include one or morecomponents such as a lever or knob 52 for manipulating the elongate body16 and/or additional components of the medical device 12. For example, apull wire 54 with a proximal end and a distal end may have its distalend anchored to the elongate body 16 at or near the distal portion,and/or may be coupled to the proximal or distal end of the deflectablesegment 30 of the fluid delivery conduit 28. The proximal end of thepull wire 54 may be anchored to an element such as a cam incommunication with and responsive to the lever 52. The medical device 12may include an actuator element 56 that is movably coupled to theproximal portion of the elongate body 16 and/or the handle 44. Theactuator element 56 may further be coupled to a proximal portion of theshaft 22 such that manipulating the actuator element 56 in alongitudinal direction causes the shaft 22 to slide towards either ofthe proximal or distal portions of the elongate body 16. The actuatorelement 56 may include a thumb-slide, a push-button, a rotating lever,or other mechanical structure for providing a movable coupling to theelongate body 16, the handle 44, and/or the shaft 22. Moreover, theactuator element 56 may be movably coupled to the handle 44 such thatthe actuator element is movable into individual, distinct positions, andis able to be releasably secured in any one of the distinct positions.

The medical device 12 may include one or more rotational controlelements 58 that are rotatably coupled to the proximal portion of theelongate body 16 and/or the handle 44. The rotational control element(s)58 may further be coupled to the proximal and/or distal ends of thedeflectable segment 30 and/or the shaft such that rotating therotational control element 58 about a longitudinal axis of the handle 44and/or elongate body 16 results in similar rotation of the attachedproximal and/or distal ends and/or the shaft at the distal portion ofthe medical device 12. The rotational control element 58 may include aknob, dial, or other mechanical structure for providing a rotatablecoupling to the elongate body 16, the handle 44, and/or the shaft 22.Moreover, the rotational control element 58 may be rotatably coupled tothe handle 44 and/or elongate body 16 such that the rotational controlelement is movable into individual, distinct positions, and is able tobe releasably secured in any one of the distinct positions.

As the fluid delivery conduit 28 and the expandable element 40 may becoupled to the shaft 22 and/or distal tip, movement of the shaft 22 canallow the controllable transition of the fluid delivery conduit 28 andthe expandable element 40 from one geometric shape, configuration, ordimension to another. By sliding and rotating the shaft 22 (in additionto and/or independently of the manipulation of the distal and/orproximal ends 32, 34 of the fluid delivery conduit 28), throughmanipulation of the actuator element 56 and/or rotational controlelement(s) 58 of the handle 44 for example, the fluid delivery conduit28 can be manipulated into various geometries for the desired clinicalor therapeutic effect. For example, the shaft 22 can be moved androtated to transition the fluid delivery conduit 28 from a near linearconfiguration adjacent the shaft to a partial circumferential, loopedconfiguration (i.e., a partial helical or spiral shape) about the shaft.The orientation of the looped configuration can further be modified byrotating the shaft 22 (and/or the proximal and distal ends of thedeflection segment) through manipulation of the rotational controlelement(s) and the actuator element(s).

By using both rotational and longitudinal manipulation mechanisms of themedical device 12, the dimensions and geometry of the deflectablesegment 30 of the fluid delivery conduit 28 can be increased anddecreased as desired. For example, the fluid delivery conduit 28 may bemanipulated through a range of diameters or curvilinear configurationssuch that a portion of the fluid delivery conduit 28 is adjacent aselected portion of the expandable element 40 for focused thermalexchange with a particular tissue region. On the other hand, anear-linear configuration of the fluid delivery conduit 28 can beselected to disperse fluid within the interior of the expandable element40 for thermal exchange with tissue contacting an outer circumference ofthe expandable element 40. The linear configuration also facilitatesease of introduction and removal of the medical device 12 through thevasculature when the expandable element 40 is collapsed or evacuated(which may be further aided by the deflective, steering mechanismsdescribed above).

The system 10 may further include one or more sensors to monitor theoperating parameters throughout the system, including for example,pressure, temperature, flow rates, volume, or the like in the controlunit 14 and/or the medical device 12, in addition to monitoring,recording or otherwise conveying measurements or conditions within themedical device 12 or the ambient environment at the distal portion ofthe medical device 12. The sensor(s) may be in communication with thecontrol unit 14 for initiating or triggering one or more alerts ortherapeutic delivery modifications during operation of the medicaldevice 12. One or more valves, controllers, or the like may be incommunication with the sensor(s) to provide for the controlleddispersion or circulation of fluid through the lumens/fluid paths of themedical device 12. Such valves, controllers, or the like may be locatedin a portion of the medical device 12 and/or in the control unit 14.

In an exemplary system, a fluid supply 60 including a coolant, cryogenicrefrigerant, or the like, an exhaust or scavenging system (not shown)for recovering or venting expended fluid for re-use or disposal, as wellas various control mechanisms for the medical system may be housed inthe console. In addition to providing an exhaust function for thecatheter fluid supply, the console may also include pumps, valves,controllers or the like to recover and/or re-circulate fluid deliveredto the handle, the elongate body, and/or the fluid pathways of themedical device 12. A vacuum pump 62 in the control unit 14 may create alow-pressure environment in one or more conduits within the medicaldevice 12 so that fluid is drawn into the conduit(s)/lumen(s) of theelongate body 16, away from the distal portion and towards the proximalportion of the elongate body 16. The control unit 14 may include one ormore controllers, processors, and/or software modules containinginstructions or algorithms to provide for the automated operation andperformance of the features, sequences, or procedures described herein.

While the medical device 12 may be in fluid communication with acryogenic fluid source to cryogenically treat selected tissue, it isalso contemplated that the medical device 12 may alternatively oradditionally include one or more electrically conductive portions orelectrodes thereon coupled to a radio frequency generator or powersource as a treatment or diagnostic mechanism.

Now referring to FIGS. 5-6, in an exemplary method of use, the medicalsystem 10 may be used to deliver therapeutic treatment to a targetedtissue area. For example, the medical device 12 may be positioned andoperated to thermally treat or ablate a targeted tissue region in theheart, such as a pulmonary vein opening or ostia. The distal portion ofthe medical device 12 may be positioned adjacent the targeted tissue,with the deflectable segment 30 of the fluid delivery conduit 28 in afirst geometric configuration, which may include a substantially linearconfiguration of the fluid delivery conduit adjacent the shaft 22, forexample. Once the distal portion of the medical device has beenpositioned where desired with the deflectable segment 30 of the fluiddelivery conduit in the selected configuration, it may be operated tothermally treat the tissue. For example, a cryogenic coolant or fluidmay be circulated through the fluid delivery conduit 28 and into theinterior of the expandable element 40 to expand the expandable element40. The circulation of coolant within the expandable element 40 resultsin the reduced temperature of the expendable element and the tissue inproximity to it. Where the fluid delivery conduit includes helical slitsor openings, the rate of coolant dispersion may be controlled at leastin part by extending or compressing the fluid delivery conduit to modifythe opening size (and thus coolant flow rate) out of the fluid deliveryconduit and into the interior or chamber defined by the expandableelement 40. The extent of the thermal exchange and/or realizedtemperatures of the expandable element 40 and thus the tissue may alsobe manipulated by one or more controls in the control unit 14 to providefor tissue ablation, mapping, or other therapeutic and/or diagnosticfunction. If the expandable element 40 is adjacent an opening or orificeof a blood vessel, such as a pulmonary vein, the balloon may be used tocreate a circular or circumferential treatment area or lesion on thethermally affected tissue.

Upon achieving the desired effect with the distal portion of the medicaldevice 12 having the expandable element 40 and the deflectable segment30 of the fluid delivery conduit in the first geometric configuration,the flow of coolant to the fluid delivery conduit 28 and thus theinterior of the expandable element 40 38 may be discontinued. The distalportion of the medical device 12 may then be repositioned in proximityto a tissue region where additional thermal treatment may be performed.The fluid delivery conduit 28 may be configured into a second geometricconfiguration to create the desired therapeutic effect. For example, thedeflectable segment 30 of the fluid delivery conduit may be transitionedinto a curvilinear, arcuate, or helical shape. The deflectedconfiguration of the fluid delivery tube may result in a portion of thedeflectable segment 30 in close proximity to or immediately adjacent aportion of the expandable element 40. The transition may be achieved bymanipulating the actuator element(s) 56 and/or the rotational controlelement(s) 58 as described above. Once the desired geometricconfiguration has been achieved, coolant may be re-introduced orotherwise circulated through the fluid delivery conduit 28 and into theinterior of the expandable element 40.

Of note, as the fluid delivery conduit 28 is immediately adjacent aninterior surface of the expandable element 40, which may be in contactwith the targeted tissue site on the opposite side of the expandableelement 40, there is a substantially reduced, if not altogethereliminated, extraneous thermal load or environment to interfere with thethermal exchange between the coolant exiting the fluid delivery conduit28, the expandable element 40, and the adjacent tissue. In other words,the close proximity of the coolant dispersion from the fluid deliveryconduit 28 towards the expandable element 40 combined with the closeproximity of the tissue to the expandable element 40 reduces the heatloss from fluid flow around other portions of the exterior of themedical device 12. Moreover, because of the close proximity of thedeflectable segment 30 to the expandable element 40 and the impartedshape change of the fluid delivery conduit, the resulting tissue regionaffected by the thermal transfer will substantially mimic or reflect thegeometric shape of the deflectable segment 30, e.g., the treated areawill be arcuate, curvilinear, or helical.

Accordingly, the second geometric configuration of the deflectablesegment 30 may be used to impart a second tissue lesion and/or thermallyaffected area having a varied geometric pattern and/or dimension to thatof the first tissue lesion or treatment area. The manipulation and/orrepositioning of the distal portion of the medical device 12 and thedeflectable segment 30 may be repeated as needed to achieve the desiredtherapeutic effect, which may include patterns of linear, curvilinear,arcuate, helical, and/or circumferential lesions or treatment areas.

The controllable geometric configuration of the distal portion of themedical device generally provides the ability to deliver therapeutictreatment in a variety of different geometric configurations, dimensionsor shapes with a single device and further provides an ability to ensurecontinuity of an ablation lesion or pattern with a single device, ratherthan with several different devices. In addition, varying range ofshapes and dimensions attainable with the manipulable fluid deliveryconduit provides varying degrees of precision in treating tissue and/orcreating an ablative lesion as a result of its respective geometricconfigurations, shapes, and/or dimensions. For example, a deployed,helical or circumferential configuration may be used during an initialstage of a procedure to treat a relatively large area of tissue, while asecond linear or otherwise decreased profile may subsequently be used totreat smaller sections or specific areas of tissues within the broadregion that require additional therapy. Although the exemplary usedescribed above employed first and second geometric configurations, itis contemplated that a shaping element capable of more than twoconfigurations may be employed and achieved through a combination ofmechanical, thermal, and/or electrical forces, as well as throughcharacteristics provided through material selection in the constructionof the shaping element. Moreover, while examples and illustrations ofparticular geometric configurations have been provided, it is understoodthat virtually any shapes, configurations, and/or dimensions may beincluded and/or achieved by the medical device of the present invention,including but not limited to those shapes illustrated and describedherein. A particular geometric configuration may include circular,conical, concave, convex, rounded, or flattened features and/orcombinations thereof. Accordingly, an embodiment of the medical deviceof the present invention may be able to provide focal lesions, circularlesions, linear lesions, circumferential lesions, and combinationsthereof.

It will be appreciated by persons skilled in the art that the presentinvention is not limited to what has been particularly shown anddescribed herein above. In addition, unless mention was made above tothe contrary, it should be noted that all of the accompanying drawingsare not to scale. Of note, the system components have been representedwhere appropriate by conventional symbols in the drawings, showing onlythose specific details that are pertinent to understanding theembodiments of the present invention so as not to obscure the disclosurewith details that will be readily apparent to those of ordinary skill inthe art having the benefit of the description herein. Moreover, whilecertain embodiments or figures described herein may illustrate featuresnot expressly indicated on other figures or embodiments, it isunderstood that the features and components of the system and devicesdisclosed herein are not necessarily exclusive of each other and may beincluded in a variety of different combinations or configurationswithout departing from the scope and spirit of the invention. A varietyof modifications and variations are possible in light of the aboveteachings without departing from the scope and spirit of the invention,which is limited only by the following claims.

What is claimed is:
 1. A method of thermally treating tissue,comprising: positioning an expandable element of a medical deviceadjacent to the tissue; delivering a fluid into an interior of theexpandable element with a fluid delivery conduit to expand theexpandable element, the fluid delivery conduit being in a firstgeometric configuration; thermally treating a first region of the tissuewith the expandable element; transitioning the fluid delivery conduitfrom the first geometric configuration into a second geometricconfiguration; and thermally treating a second region of the tissue withthe expandable element.
 2. The method of claim 1, wherein the medicaldevice includes a guide wire lumen at least partially disposed withinthe elongate body and at least partially disposed within the interior ofthe expandable element.
 3. The method of claim 2, wherein the fluiddelivery conduit includes a deflectable segment defining a proximal endand a distal end with the proximal end being slidably and rotatablycoupled to the shaft and the distal end being immovably fixed to theguide wire lumen.
 4. The method according to claim 1, wherein the firstregion has a shape different from a shape of the second region.
 5. Themethod according to claim 1, wherein the shape of the first region issubstantially circular.
 6. The method according to claim 3, whereintransitioning the fluid delivery conduit from the first geometricconfiguration into a second geometric configuration includes rotating atleast a portion of the fluid delivery conduit about the guide wire lumenof the medical device.
 7. The method according to claim 3, whereintransitioning the fluid delivery conduit from the first geometricconfiguration into a second geometric configuration includeslongitudinally sliding at least a portion of the fluid delivery conduitalong a guide wire lumen of the medical device.
 8. The method accordingto claim 3, wherein delivering a fluid includes extending a portion ofthe fluid delivery conduit defining at least one opening that ishelically arranged around an outer circumference of the fluid deliveryconduit to increase a rate of fluid flow into the expandable element. 9.The method according to claim 3, wherein delivering a fluid includescompressing a portion of the fluid delivery conduit defining at leastone opening that is helically arranged around an outer circumference ofthe fluid delivery conduit to decrease a rate of fluid flow into theexpandable element.
 10. The method according to claim 1, whereinthermally treating the tissue includes ablating at least a portion ofthe tissue, and the tissue includes an ostium of a pulmonary vein. 11.The method according to claim 1, wherein the first geometricconfiguration is substantially linear and the second geometricconfiguration is curvilinear.
 12. The method according to claim 1,further comprising: terminating coolant dispersion into the interiorcavity; transitioning the fluid delivery conduit from the secondgeometric configuration to the first configuration; and removing theexpandable element from the tissue.
 13. A method of thermally treatingtissue, comprising: positioning an expandable element of a medicaldevice adjacent to the tissue, the medical device including a guide wirelumen at least partially disposed within the expandable element;delivering a fluid into an interior of the expandable element with afluid delivery conduit to expand the expandable element, the fluiddelivery conduit including a deflectable segment defining a proximal endand a distal end with the proximal end being slidably and rotatablycoupled to the shaft and the distal end being immovably fixed to theguide wire lumen, the fluid delivery conduit being in a first geometricconfiguration; thermally treating a first region of the tissue with theexpandable element; transitioning the fluid delivery conduit from thefirst geometric configuration into a second geometric configuration; andthermally treating a second region of the tissue with the expandableelement.
 14. The method of claim 13, wherein transitioning the fluiddelivery conduit from the first geometric configuration into a secondgeometric configuration includes longitudinally sliding at least aportion of the fluid delivery conduit along a guide wire lumen of themedical device.
 15. The method of claim 13, wherein delivering a fluidincludes extending a portion of the fluid delivery conduit defining atleast one opening that is helically arranged around an outercircumference of the fluid delivery conduit to increase a rate of fluidflow into the expandable element.
 16. The method of claim 13, whereindelivering a fluid includes compressing a portion of the fluid deliveryconduit defining at least one opening that is helically arranged aroundan outer circumference of the fluid delivery conduit to decrease a rateof fluid flow into the expandable element.
 17. The method of claim 13,wherein thermally treating the tissue includes ablating at least aportion of the tissue, and the tissue includes an ostium of a pulmonaryvein.
 18. The method of claim 13, wherein the first geometricconfiguration is substantially linear and the second geometricconfiguration is curvilinear.
 19. The method of claim 13, furthercomprising: terminating coolant dispersion into the interior cavity;transitioning the fluid delivery conduit from the second geometricconfiguration to the first configuration; and removing the expandableelement from the tissue.
 20. A method of thermally treating tissue,comprising: positioning an expandable element of a medical deviceadjacent to the tissue, the medical device including a guide wire lumenat least partially disposed within the expandable element; delivering afluid into an interior of the expandable element with a fluid deliveryconduit to expand the expandable element, the fluid delivery conduitincluding a deflectable segment defining a proximal end and a distal endwith the proximal end being slidably and rotatably coupled to the shaftand the distal end being immovably fixed to the guide wire lumen, thefluid delivery conduit further including at least one opening that ishelically arranged around an outer circumference of the fluid deliveryconduit, the fluid delivery conduit being in a first geometricconfiguration; thermally treating a first region of the tissue with theexpandable element; transitioning the fluid delivery conduit from thefirst geometric configuration into a second geometric configuration; andthermally treating a second region of the tissue with the expandableelement.